EN
The antimicrobial activity of two new series of bis-piperidinium compounds, with alkyl chains of dierent length, against bacterial (Escheri- chia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis) and fungal strains (Aspergillus !avus, Aspergillus niger, Rhodolorula rubera, Lipomyces lopofera and Candida albicans), are described. Antimicrobial activities of the synthesized compounds were compared to that of dodecyltrimethylammonium chloride. Bis-piperidinium salts containing 12–16 carbon side chains showed better antimicrobial properties when compared to the standard dodecyltrimethylammonium chloride.